1. Field of the Invention
This invention relates to devices to protect persons from exposure to environmental contaminants. More particularly, this invention pertains to a barrier-type device for preventing the spread of airborne contaminants in medical and dental treatment operations for protection of personnel against airborne debris and contaminants in medical, dental and laboratory operations.
2. Description of the Related Art
Bacteria and viruses may be transferred from patients to dentists in the debris that is ejected from the patient's mouth during dental care and surgery. This debris may contain blood, saliva, hard tissue and filling materials. In an attempt to avoid or decrease exposure of dental workers to possible pathogens, face and eye shield devices have been designed for the dentist to wear attached to the dentist's head (U.S. Pat. No. 4,701,965) or suspended around the dentist's neck (U.S. Pat. No. 4,701,129). These patents and all other references cited herein are incorporated by reference herein. Such face shield devices may become fogged or dirtied on the inside by the wearer or may be difficult to use by wearers with glasses. In addition, face shields may interfere with breathing due to lack of sufficient ventilation between the shield and the face.
In the medical profession as a whole, other types of shields to protect the medical workers or the patient from contamination and infection have been developed including plastic body wraps (U.S. Pat. No. 4,725,719), draping screens (U.S. Pat. No. 3,575,407) and laminar air flow hoods (U.S. Pat. No. 3,820,536).
Other industries also have need for shields to protect the worker from splashes or flying particles or debris or to protect the work surfaces. Protective devices include a variety of eye shields, and shields for the work area, such as a circular guard having a transparent material held in a frame, which may be mounted on metal working machines to protect the operator (U.S. Pat. No. 1,175,274), a U-shaped safety shield assembly (U.S. Pat. No. 4,043,701) and an eye and face shield for work with an emery wheel, comprising a transparent plate held in a frame, with a base that attaches by means of a flexible part to the table of a floor stand (U.S. Pat. No. 1,580,903).
In the construction industry, a paint guard for protecting frame windows or doors includes a rectangular framework with telescopingly interconnected frame members so that the size of the frame may be adjusted (U.S. Pat. No. 4,411,219). It has a biasing spring mechanism to hold the frame in a contracted position on a door or window. A flexible material may be held within this frame by rollers positioned at the edge of the frame.
Many of the barrier guards that are positioned near a work area to protect the worker must be regularly cleaned, especially if the debris is wet or sticks to the surface of the guard. Not only is such a cleaning procedure time-consuming, but in medical applications, he cleaning procedure may expose the person cleaning the apparatus to any contaminating organisms present on the shield. These shields may also scratch, resulting in decreased transparency. In addition, these guards may be difficult to disinfect and sterilize by design, or because their size precludes sterilization by small office autoclaves. Guards are often difficult to place in the exact desired position due to structural limitations of the guards themselves or of their support structures. Many guards comprise glass or other heavy or breakable material that increases the difficulty of easy maneuverability of the guard. Most of these devices do not comprise frames that are capable of use with transparent light-weight film material or that can hold such a material taut and smooth. In dental work, because the operator works at a wide variety of positions with respect to the patient, the position of a shield designed for dental use needs to be easily adjustable for effective use of the shield.
It is therefore an object of this invention to provide a positionally adjustable barrier assembly for dental, medical and laboratory workers. The invention is useful for worker protection in situations as varied as dental and medical offices, hospital microbiology and blood labs, industrial and educational chemistry labs and factories that employ rotary instruments.
It is a further object of this invention to provide a barrier assembly having a transparent film shield which may be inexpensively and quickly replaced
It is a further object of this invention to provide a barrier assembly that holds transparent film smoothly in place.
It is a further object of this invention to provide a barrier assembly that is sterilizable.
Other objects and advantages will be more fully apparent from the following disclosure and appended claims.